Mrs Marcos, 69, had been told she would be arrested if she failed to appear before the committee, which is investigating the fortune accumulated by her late husband, Ferdinand Marcos, during his 20 years as Philippine president.

At the hearing, she refused to answer at least 15 times when faced with questions about her family's wealth.

"Because of the hundreds of cases pending here and abroad,
I have been ordered by my lawyers to invoke my right to remain
silent," she said.

Mrs Marcos is facing court hearings over alleged financial impropriety. She is taking separate legal action to recover billions of dollars she says are private family assets.

Appearing before the Senate committee

The hearing was ordered after she reportedly told a local newspaper that she was the rightful owner of 500bn pesos ($12.5bn) worth of shares in top Philippine companies and wanted them back.

"We practically own everything in the Philippines," Mrs
Marcos was quoted as saying by the Philippines Daily Inquirer.

But the former first lady said tapes of the conversations she had with a reporter were not intended for publication.

President Marcos was ousted from the presidency by a revolution in 1986. He died in exile in Hawaii three years later.

The government has filed many cases against the Marcos family seeking to recover wealth it alleges was amassed illegally during his years in power.

Mrs Marcos claims her husband was already wealthy from gold trading before being elected president.

After the hearing, the senate investigating committee decided to give her until next month to justify her refusal to testify.

BBC Philippines Correspondent John McClean says if her lawyers fail to do this she could be arrested and detained for corruption.